1. Field of the Invention
Embodiments of the invention relate to the field of semiconductor, and more specifically, to semiconductor fabrication.
2. Description of Related Art
On-chip devices such as voltage regulators have become increasingly popular in applications requiring low power, high frequency, and efficiency. Typically, these devices use magnetic material targeted for high frequency applications. One major problem with the design of on-chip devices is degraded efficiency or power loss from eddy currents at high frequency.
Existing techniques in the fabrication of magnetic components in high frequency on-chip devices have a number of drawbacks. One technique uses a continuous magnetic layer. This technique produces a large eddy current which leads to high power loss. Another technique uses granular magnetic particles to reduce the eddy currents. However, this technique does not allow subsequent processing such as metallization. Other techniques use materials such as Physical Vapor Deposition (PVD) cobalt-zirconium-tantalum (CoZrTa) alloy or electroless Cobalt Tungsten Boron Phosphorous (CoWBP). These materials have low resistivities in the range of 100-140 μΩ·cm. The low resistivity leads to high power loss due to eddy currents.